Articles of this kind are intended to be worn by menstruating women or by persons who suffer from relatively light incontinence, and who require the articles to afford protection against leakage but still be unnoticeable when worn beneath conventional clothing. Since the amount of fluid discharged with menstruation and with light incontinence is relatively small, the articles can be designed in a manner which enables them to be accommodated essentially fully in the crotch region, between the wearer's thighs. The requirement that such articles shall be discrete when worn is satisfied almost to the full by said articles.
However, it has been found difficult to produce articles of this kind which are sufficiently proof against leakage. The main reason for this is that, when worn, the articles are highly deformed by the forces that are generated as the wearer moves. The greatest deformation normally occurs within that part of the article which, in use, is located in the narrowest space between the wearer's thighs. Unfortunately, this part of the article is also the part which is intended to receive the discharged body fluid first and to absorb said fluid. As a result of this pronounced deformation of the article, the surface area of the article available for direct absorption is, of course, greatly reduced. This increases the risk of body fluid leaking past the side edges of the article and soiling the user's underpants.
A number of different methods of reducing the risk of lateral leakage have been proposed. For example, SE 455 668, U.S. Pat. No. 4,285,343, EP 130 848, EP 134 086 and U.S. Pat. No. 4,608,047 teach sanitary napkins which are provided with flexible flaps, or wings, that protrude outwardly from the absorbent pad. These flaps are intended to be folded around the edges of the leg openings of the wearer's underpants or like garment and fastened to the outside of said underpants when fitting the napkin for use. The flaps thereby form a protective guard against the lateral leakage of body fluids and soiling of the underpants.
These earlier known, so-called winged sanitary napkins are encumbered with several drawbacks, however. For example, sanitary napkins of this kind are found difficult to manipulate by many users, mainly because of the difficulty found in folding and shaping the wings around the curved edges of the leg openings of a pair of underpants or like garment. This problem is particularly manifest in the case of sanitary napkins whose wings or side-flaps have large extensions in the longitudinal direction of the article, since it is necessary to fold the wings around a relatively large part of the leg edges of the underpants. Wings which extend along only a small part of respective side edges of the napkin can be folded around the edges of the leg openings more easily, but these flaps, naturally, provide much poorer protection against leakage than the large flaps.
The known winged sanitary napkins are normally secured to the underpants of the wearer by means of pressure-sensitive adhesive provided on the wings, in the form of adhesive beads, strings or the like along the longitudinal center line of the napkin, on that side of the napkin which is distal from the wearer in use. Prior to use, the pressure-sensitive adhesive is covered with a protective release strip, which is removed when the binder is to be secured to the wearer's underpants.
When securing winged sanitary napkins of this kind to the wearer's underpants, the work involved in removing the various protective layers and in folding and securing the wings is quite comprehensive. Furthermore, the work involved must be carried out in the correct sequence in order to avoid prematurely exposed adhesive surfaces from fastening to the underpants in the wrong places and therewith making it difficult to position the napkin correctly.
The known winged sanitary napkins normally comprise an absorbent pad which is enclosed by two casing sheets. These sheets extend beyond the side edges of the absorbent pad, to form the wings of the napkin. This, of course, is a simple construction which affords certain manufacturing advantages. However, a great deal of material is wasted when cutting such napkins to shape, which is obviously a disadvantage. Furthermore, it is necessary to fold the wings together so that the napkins can be packaged, which complicates the manufacturing process.
Furthermore, the fact that the napkin casing material merges directly with the wings is disadvantageous from a purely functional aspect, since body fluid can then be transported from the absorbent pad to the wings, causing leakage.
The present invention provides an article of the aforedescribed kind which avoids the drawbacks associated with known articles of this kind.